<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
  <style>
    #grid {
      display: grid;
      grid:
        "header header header header" 40px
        "leftside content content content" 50px
        "leftside content content content" 50px
        "footer footer footer footer" 40px /
        1fr 3fr 3fr 3fr;
      background-color: antiquewhite;
      gap: 10px 20px;
    }

    .absolute-son {
      grid-area: content;
      background-color: deepskyblue;
      position: absolute;
      top: 20px;
      left: 80px;
    }

    .margin-son {
      grid-area: header;
      background-color: deeppink;
      margin: auto;
      /* width: 300px; */
    }
  </style>
</head>
<body>
  <div id="grid">
    <div class="absolute-son">this is a son of position with absolute</div>
    <div class="margin-son">this is a son of margin with auto</div>
  </div>
</body>
</html>